1. To vary irregularly
2. To change often from high to low levels
3. Frequently changing the level, strength, or value of something
The best way to remember the word fluctuate is to relate it the frequent electricity cuts and voltage fluctuation (changes) that used to happen in our homes back in the day.
1. His popularity has fluctuated during his term in office.
2. The planetary climates fluctuate, seasonally and temporally.
3. Data from the black box indicates that the plane’s reading were fluctuating wildly before it ultimately crashed.